1. Field of the Invention
This invention relates to the dyeing of textile materials. More particularly, it relates to a dye bath composition and to a dyeing process in which uncontrolled migration of the dye to the material surface during drying prior to fixation is minimized.
Description of the Prior Art
In commercial dyeing operations in which a textile material is impregnated with a dye by padding with an aqueous dye bath liquid, as in the conventional Thermosol process, the dye-impregnated material is commonly dried, e.g., by heating, prior to fixation of the dye. It is well known that the dye particles tend to migrate to the surface of the material during the drying operation and that such migration tends to be of an uncontrolled and random nature. Such uncontrolled migration, however, leads to an uneven dyeing, detracting from the appearance and value of the dyed textile material. As a result, various additives, including natural gums, sodium alginate and a variety of synthetic antimigrants have been proposed in order to reduce such uncontrolled migration. Many of the materials thus proposed in the literature were described also with respect to thickening characteristics, the terms "thickeners" and "antimigrants" commonly being employed synonymously. While many materials thus proposed as antimigrants also tend to find application in other systems as thickeners, the more persuasive teachings available suggest that the viscosity of the dye bath per se does not have any significant effect with respect to the uncontrolled dye migration problem discussed above.
While various materials have thus been proposed as antimigration additives, no such materials have found widespread acceptance because of the relatively high incremental costs associated with the use of such antimigrants, undesirable side effects that often occur as a result of the presence of particular antimigrants in specific aqueous dye bath liquor systems or a combination of these or like factors disadvantageous in the overall dyeing operation. There exists in the art, therefore, a need and a desire for less expensive, more technically efficient antimigrants having an enhanced compatibility with aqueous dye bath liquid systems for the dyeing of textile materials.
It is an object of the present invention, therefore, to provide an improved aqueous dye bath liquid capable of minimizing undesired dye migration.
It is another object of the invention to provide an improved dyeing process in which migration of the dye during drying prior to fixation is minimized.
It is a further object of the invention to provide an improved dye bath liquid having a desirable combination of effective dye migration prevention and minimal incremental cost.
With these and other objects in mind, the invention is hereinafter disclosed in detail, the novel features thereof being particularly pointed out in the appended claims.